Numerical simulation of excavation of shield tunnel

Shield tunnel is an attractive excavation method in the construction of municipal underground engineering. The ground subsidence is the most noticeable problem in the excavation of shield tunnel. The influence of shield tunnel is numerically simulated by adopting the small-strain constitutive model provided by authors, and the modified Cam-clay model, respectively. The computed results of these two models are similar. The ground subsidence and the impacted area in the computed results of the modified Cam-clay model are affected by construction quality slightly, but the computed results of the model provided by authors are sensitive to construction quality. These are related to the judgment of loading-unloading, and the simulation of the small-strain mechanical characteristics are more reasonable in the small-strain constitutive model. The further analysis shows that the computed results of the small-strain constitutive model are more reasonable, and the small-strain mechanical behaviors of soils should be taken into account.